Patent GB-770147-A (GB)
Title: Improvements in or relating to machines for separating and cleaning grain, seeds andthe like
Inventor: DEMPSEY WALTER EARL
IPC: B02B1/02
Filed: 1955-06-23
Abstract: 770,147. Pneumatic separating, sifting. PENNEY & PORTER, Ltd. June 23, 1955, No. 18147/55. Class 117. A grain cleaner and classifier comprises two rotary cylindrical screens 15, Fig. 1, with adjustable circumferential screening spaces providing a width dividing assembly fed at 26, Fig. 2, with grain and impurities which is propelled overthe screens by a worm conveyer 25, weight dividing winnowing apparatus 2, 2a for separating respectively, trash &c. from the fraction of the grain designated "thrus" that passes through the screen spaces and from that fraction designated "overs" that is propelled over the ends of the screens, and a length divider 3 having separate sections for receiving the "thrus" and "overs." From the screen spaces the "thrus" passes into a pan 4 supported by flexible hangers 57 and reciprocated by eccentrics on a drive shaft 50; it then flows through an outlet 46, Figs. 2 and 3, into an oppositely reciprocated hopper 5 of a winnowing chamber 6a. The "overs" pass through ducts 30 into a hopper 7 which reciprocates with the pan 4, and flows into an oppositely reciprocated hopper 8 and winnowing chamber 6b. Bars 59 interconnect the winnowing chambers which are suspended by flexible straps 62 and reciprocated by further eccentrics on the shaft 50. Each winnowing chamber is open. at the front and rear of the machine and the rear openings accommodate the outlets 69 of fans 68. The "thrus" and "overs" fall, respectively, through slots 47 and 49, Figs. 1 and 3, into chambers 6a, 6b and into the path of air blasts whereby the lighter seeds and trash and blown from openings 67. Each chamber has pivoted baffles 75 and the chamber 6b has a further baffle 77, Fig. 1, enabling the lighter "avers" to be delivered to a discharge opening 79. The heavier "overs" pass to an opening 80 and, depending on the position of a valve 83, to either a discharge shoot 82 or a shoot 81 delivering the "overs" to a section 86 of the length dividing assembly 3. "Thrus" from chamber 6b passes into the - entrance end of the assembly which includes conventional grain separating pocketed discs 89 secured to a shaft 33 by spokes 90, Fig. 1, having propeller blades feeding the material through the divider. The discs are arranged in series with the pockets of succeeding discs of increasing size. An inclined catch trough 91 is positioned between adjacent discs and delivers the grain according to length into hoppers 10-13. The length divider consists of two main sections 85, 86 , Fig. 2, into which the "thrus" and "overs" are fed respectively, separated by an apertured wall 87, the aperture being closable by a pivoted plate. Further subsections are provided by dividing walls 98 arranged between hoppers 11-13. A discharge spout 103 is positioned at one end of the section 85, and grain &c. of excessive length is delivered from a spout 100. A worm type conveyer 101 within a trough 9 extends along the length divider, and when trough flaps 105 are closed grain passes over them to one or more of the hoppers. When the flaps are opened the material falls into the trough and is conveyed to a delivery spout 111. In a modification two adjacent troughs such as 9 extend along the length divider and each trough includes a rotary conveyer, one of which delivers material to the discharge spout and the other returns it to the entrance end of the divider. Material is delivered to one or the other trough, or to discharge hoppers, depending on the positions of trough closure flaps. Each screen 15 is cleaned by a brush 16, Fig. 1, and consists of a continuous length of helically wound wire; it is in two sections 15a, 15b, Fig. 2, divided by a spider 19, intermediate end spiders 17 and 20. Spiders 19 and 20 are longitudinally slidable on the drive shaft 22 to vary the spacing between adjacent wire turns. Radial vanes 27 at the end of each screen deliver "overs" into a worm conveyer 29 which rotates with the shaft 22 and delivers the feed into a duct 30. The various parts of the machine are driven from a main drive shaft 37 by belting &c.